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Scientist Sees Space Elevator in 15 Years
bofh31337 writes "Scientist Bradley C. Edwards, head of the space elevator project at the Institute for Scientific Research, thinks an elevator that climbs 62,000 miles into space could be operating in 15 years. He pegs the cost at $10 billion, a pittance compared with other space endeavors. 'It's not new physics--nothing new has to be discovered, nothing new has to be invented from scratch,' he says. 'If there are delays in budget or delays in whatever, it could stretch, but 15 years is a realistic estimate for when we could have one up.' NASA already has given more than $500,000 to study the idea, and Congress has earmarked $2.5 million more."
that'll be the wait after pressing the UP button.
Imagine the jerk that presses the "close door" button as you're running.
"it could stretch"
When all you have is a hammer, everything looks like a skull.
This is a high performance, high stress ribbon
This application has little room for error. Obviously.
Wear on carbon nanotube ribbons may be significant.
Carbon nanotube ribbons may be susceptible to significant deterioration from cosmic rays.
Micrometeor impacts may also be a problem.
If the ribbon fails, what do we do with 62,000 miles of ribbon?
Oh wait, we build a Beowulf cluster of Christmas wrapping stores.
And then there is the cost estimate.
Low.
And you thought that the CN Tower was a long elevator ride. I wonder how long it would take to go that far into space in an elevator? Would there be in-elevator movies and food service?
There would need to be. At any reasonable speed, you're looking at a 24 to 48 hour trip.
"They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
The current issue of Discover magizine has a much longer and more informative writeup.
...Nobody but you can hear the elevator music
And consequently, nobody can hear you scream.
It would be cool if it didn't suck.
And I think he means 62,000 miles. 62 Miles is only the boundary of space. What would the point of finishing there be? The reason he says 62,000 is because it covers everything useful in space travel, from Low earth orbit up past geosynchronous orbit.
TheHustler
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No, it *is* 62000 miles. The tether has to be that long to allow a suitable anchor to be attached at the other end and keep the right amount of tension on it. Or something. /not rocket scientist, but mightily impressed at this bloody good idea.
Brian Smith "Jokers and aces, bruisy and blackfern" - Steve Kilbey, Day of the Dead.
One little problem for a human to ride the space elevator--the slow speed of assent means that people would pass though the Van Allen belt for a rather long time--exposing them to possibly deadly radiation.
Another Arthur C. Clark moment, he has come up with so many amazing inventions in his chronicles. The satellite, now this... Actually I'm not sure if he did come up with the idea, but it was in 3001. So if you want to read about the theories of space elevators. This is the book to pick up.
He pegs the cost at $10 billion...NASA already has given more than $500,000 to study the idea, and Congress has earmarked $2.5 million more.
Wow, at this rate, we'll have the money in, oh, 1000 years...
Do you have ESP?
> At any reasonable speed, you're looking at a 24 to 48 hour trip
That's a _shitload_ of crappy muzak, there! Better bring a fully-loaded iPod.
And hope there's no crazy guy singing 'Roxanne' while you're in there.
Uhhm, even in his book, Edwards admits that the carbon nanotubes needed to make this work just aren't there yet; while we can manufacture nanotubes now, we can't make them as strong (by a factor of around 100) or nearly as long (by a factor of 10,000 or more) as needed. While it may well be that, as soon as someone really puts some effort/research bucks into making stronger/longer nanotubes, they will happen, but it seems like 15 years might still be optimistic.
OTOH, this would be way cool, and maybe in my lifetime to boot...
"I'm a scientist! I don't think, I observe!" - Dr. Clayton Forrester
Build a roller coaster from space, to the earth... Slow ride up.. then massive whoosh on the way down with plenty of loops and turns and upside-down goodness! Imagine the tourism dollars that could go fund the lowly freight elevator next to it! And we could call it.. The.. Great Space Coaster! And hire a GNU named Gary! Or Richard...
But I digress...
If you were me, you'd be good lookin'. - six string samurai
NASA says geosynchronous orbit is 36000 km = 22000 miles. I think the 62000 miles part must be so the centrifugal force keeps the cable taut. You could build a solid tower up to 62 miles, but a cable-elevator just wouldn't work at that distance.
I've read quite a few posts about "riding the space elevator." I'm under the impression (and yes, I RTFA) that the space elevator would be solely used to send cargo up to space. Astronauts would still get up to the ISS by conventional means, and then the space elevator would just be a cheap[er] way to get supplies up to them without worrying about sending up rockets. Unless I missed something, humans wouldn't be travelling on this space elevator at all.
Some folks think it's a typo, that it's supposed to be 65 miles, not 65K miles. No, 65K miles is more like it. You really want your elevator's center of mass to be in geosynchronous orbit... Space elevators to LEO tend to, uh, get wound around the earth right fast.
And if the ribbon breaks, things generally aren't so bad. The portion of the elevator (including the counter weight) that's further from the earth will tend to move away from the earth. (If you spin in a circle with a rock in your hand, then let go of the rock, the rock goes away from you, not crashing in towards your head.) The nearer part will tend to fall, but it will tend to fall slowly and is relatively unlikely to cause damage. (At least, according to High lift systems, who came and gave a talk last year.) The elevator, since it's so huge, tends to not be terribly heavy. The system proposed by high lift systems
I believe Brad Edwards was involved in High Lift Systems, so I imagine the basic idea is the same.
If geo is ~20K miles, why does the elevator need to be so long? Does this mean that they're now thinking about a lighter counter weight? They used to talk about capturing an asteroid.
#2: In emergency, USE STAIRS
Nothing in the article mentions the feasability of getting a decently sized counterweight at the top of the elevator. All plans I've heard of require at least some sort of asteroid...and if you're talking politics, people are going to be afraid of dragging a rock into Earth orbit that could smash into the planet a.la if something went awry.
I'll just wait for the Space Escalator, thank you very much.
Just you parents make sure your kids aren't wearing loose jeans on the escalator!
---- El diablo esta en mis pantalones! Mire, mire!
Better RTFA, and maybe do a little research. We are actually within a factor of two of having materials strong enough; anything after that becomes essentially an engineering problem.
...phil
"For a list of the ways which technology has failed to improve our quality of life, press 3."
How is coriolis force going to be handled.
Since velocity=(radius)(angular speed) then there has to be a tangential acceleration as the elevator starts going up.
Obviously tension on the cable can be used if you do not go up too fast or send up too much mass at one time.
Of course the talk as always about using this to go up, but would it be possible to use this as a really big sling shot to launch space craft around the solar system.
This is a vital technology but...3 ft Pipelines (say 36" X65), mere steel steel shells say 1/3 to 1 inch thick, usually cost (usually way over) over $1 million / mile on terra firma. Not to mention how much super carbon fiber rod(nearly solid 3ft??), flying it up, joining in place. Try some multiple of $100 billion at least. $10b sounds like someone's "too cheap to meter" on nuclear power 50+ yrs ago. We got "nuked" financially.
No, it's not the only problem remaining. There are a ton of nanotube problems left, and there's some doubt that they even attain the sort of >100GPa tensile strength that Edwards' design requires (one test measuring actual SWNTs put the strongest ones in the test at around 60GPa (MWNTs have tested higher, but they're not applicable due to mass)).
Then there's the "fiber" problem. Nanotube fibers are at best held together by Van der Waals force. Edwards proposes some sort of unexplained "nanotube epoxy" that is somehow supposed to be able to withstand these incredible tensile strengths which the tubes themselves, even in theory, can barely withstand. I don't buy it one bit. The best fibers made so far, held together by the same forces, achieve the sort of tensile strength you get from Kevlar. Longer tubes will help, but you'd need a *huge* improvement.
The epoxy concept is bunk. There is a concept which might work, however: pressure induced interlinking of carbon nanotubes. Basically, you swap out some of the stronger sp2 bonds for the weaker sp3 bonds, but it interlinks the tubes.
I have other problems with Edwards' design, too, but he has done an awful lot of well-reasoned calculations. I contributed a lot to the article on Wikipedia, so if you want to read more about space elevators, that's the place.
I'm an owl exterminator!
Have you read about what this system is like first?
I'm an owl exterminator!
With all the force of fluttering newspaper. It would take hours to come down, and would be more of a pollution problem than a catastrophe. Of course, this assumes failure at the thickest portion of the cable, just around geosync somewhere. The thinnest part, most likely to fail I'd think, if it were to fail, would leave it hovering just above the ground waiting to be duct taped back in place.
If there is a catastrophe to be had here, I'd think, it would be it burning (do nanotubes burn very well?). What sort of electrical storms are there that far up? The electrical potential between sky and ground can be huge, and we're stretching a non-insulator across the two.
But he's a salesman-scientist trying to convince people to invest in his big idea. Are you going to tell them "We COULD build it in 15 years" or "well, it probably won't happen for 40 because {the military-industrial complex, NASA, them welfare queens takin' all our tax money, the Canadians} won't let it." If you want something to happen, it's a better idea to talk it up rather than down!
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
You see, we've done this before... You know, the "monument of engineering in somebody else's country" thing? So where do we build this thingy along the equator??
...Let alone defending the site from the world village idiots.
Let's take a look:
Guatamala
Honduras
Congo
Gabon
Dem. Rep. Congo
Uganda
Kenya
Somalia
Indonesia
Are you fucking kidding me??????
Yes, I can see this one happening in the very near future. Just the places to plant a multi billion dollar space elevator, right? The only country I'd even consider building this thing would be in Singapore, depending on how much equatorial leeway we have to play with. I mean the science is one thing; Great yeah, we have the money and the technology, lets build this mama! But actually breaking ground on this thing is a political nightmare of epic proportions. Stability of the local governement is just as big, if not a bigger issue than "can we build it/how much?"
The fact that the builder is going to want to make money off it once it's built is another huge issue, severely limiting the number of sites. Unless you want to ship all your ultra high-tech parts halfway around the world to, say, Somolia?
Price to build isn't the only thing the government is looking at here and Bradley is a fool if he thinks that's all that's stopping this from moving forward.
You need a FREE iPod Nano
NASA already has given more than $500,000 to study the idea...
That's not all that much money at NASA, it's the equivalent of 2 Full Time Equivalents (FTEs), plus a little bit of equipment to work with.
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When, exactly, did the production of steel on a scale that one could build a bridge out of the stuff begin? Iron, too, for that matter? Certainly not thousands of years ago.
Furthermore, it was mostly the math that needed improvement, not the materials.